1. Field of the Invention
The present invention relates to a halogen heater control apparatus of a microwave oven and a method thereof, and in particular to the halogen heater control apparatus of the microwave oven and the method thereof which is capable of optimum heating and cooking foodstuff by altering in increments the infrared wavelengths from a halogen heater for controlling the phase of a utility AC power source to the halogen heater.
2. Description of the Prior Art
In general, the conventional microwave oven heats and cooks foodstuff by using microwaves. The conventional microwave oven comprises a high voltage transformer and a magnetron. When AC power is applied to the high voltage transformer, the high voltage which operates the magnetron is generated, and the magnetron generates high frequency microwaves into the sealed space storing the foodstuff.
The outputted microwaves vibrate H.sub.2 molecules of the foodstuff, the vibrations of the H.sub.2 molecules generate frictional heat, and the foodstuff is cooked by the frictional heat of the molecules.
Meanwhile, the conventional magnetron microwave oven heats and cooks the foodstuff by using only the microwaves generated from the magnetron, but the latest microwave oven comprises a magnetron and a halogen heater, accordingly it can heat and cook the foodstuff by using infrared wavelengths generated from the halogen heater in addition to the microwaves.
FIG. 1 is a schematic front view of the conventional microwave oven. FIG. 2 is a circuit diagram illustrating the conventional halogen heater control apparatus of the microwave oven comprising a microcomputer 70 which outputs a control signal corresponding to a key input of a user. A first, a second and a third relay 10-1, 10-2, 10-3 provide and cut off utility AC power source (AC: 120 V/60 HZ) to a first, a second and a third halogen heaters H1, H2, H3 in accordance with the control signal of the microcomputer 70. The first, second, and third halogen heaters H1, H2, H3 separately output the infrared wavelengths in accordance with an ON/OFF operation of the first, second and third relays 10-1, 10-2, 10-3.
The operation of the conventional halogen heater control apparatus of the microwave oven will now be described. When a magnetron output mode is selected as a microwave oven output mode by a user, the magnetron operates by the high voltage generated from the high voltage transformer (not shown), and the foodstuff is heated and cooked by the microwave outputted from the magnetron.
Meanwhile, when a halogen heater output mode is selected as a microwave oven output mode by the user, the foodstuff is heated and cooked by the infrared outputted from the halogen heaters H1, H2, H3. This will be described with the first halogen heater H1 as an example.
First, the microcomputer 70 outputs the control signal in accordance with kind of foodstuff, the first relay 10-1 is ON according to the control signal and applies the utility AC power source to the first halogen heater H1, and the halogen heater H1 outputs the infrared radiation. Accordingly, the foodstuff is heated and cooked by the infrared radiation. The infrared wave output process of the second and third halogen heaters H2, H3 are the same as with the infrared wave output process of the first halogen heater H1.
However, since the infrared waves from the halogen heaters operate in accordance with the ON/OFF operation of the relays, it only has two kinds of operation such as ON/OFF. Accordingly, it cannot heat and cook the foodstuff efficiently. When the electricity inputted to the halogen heater is provided after being cut off, the heating and cooking times required are longer, and mechanical trouble frequency may increase due to the consecutive ON/OFF operation of the halogen heaters.